Singular Perturbation Theory-Based Barrier-Adaptive Sliding-Mode Voltage Control and MPCC for Totem-Pole PFC Converters

This paper proposes a coordinated cascaded control framework for a single-phase totem-pole power factor correction (PFC) converter, where a singular-perturbation-based reduced-order model is established to explicitly separate the slow dc-link voltage dynamics from the fast input-current tracking dynamics. Based on this decomposition, the outer-loop is formulated as a current-amplitude generation problem, whereas the inner-loop is treated as a switching-state current realization problem. To address the fundamental trade-off between dc-link voltage regulation and input-current quality in single-phase PFC converters, the outer voltage loop is designed using barrier-adaptive super-twisting sliding-mode control (BA-STSMC), and a moving average filter (MAF) is incorporated to suppress the double-line-frequency ripple before it propagates into the current reference. The proposed adaptive outer-loop law provides disturbance-dependent corrective action by increasing the current-amplitude correction during large transients and relaxing the adaptive gains as the operating point approaches steady state. To accurately realize the resulting current command, the inner-loop employs finite-control-set model predictive current control (FCS-MPCC) with reference extrapolation. Simulation and experimental results obtained from a 3.3-kW prototype verify that the proposed method achieves faster startup, improved dc-link voltage regulation under load and line disturbances, and high steady-state performance over wide operating conditions.